Solar Thermal Install

[Gareth J]

I've been mulling tray mounts atop the dormer.

Running a new supply is on the cards sometime anyway. Currently bodged overhead it's great for the squirrels to access the roof! Plan is underground.

A fair bit can be saved by doing a DIY install. If that means buying some more expensive mounts, it still might be worth it.

I've an account with the K2 program, anyone can register but if you want me to roughly mock up a set to check if the sunny boy inverter is appropriate for the garage hip, I will if I get time. Pm me your postcode, the pitch and dimensions of the roof. Don't get too hung up on the sunny boy though, a new SMA of that size is about £400+vat. A Chinese one, ~£250. Worth using if you can but not worry comprising the amount of panels you can fit IMO.

I've no knowledge about tiled roofs, some look easier than others.

 

[Roger440]

Am I dreaming or is their a building reg (or similar) that says if you re-roof more than 25% of the roof area you then have to upgrade the whole roof in terms of insulation?

I think so. Just ignore. Whos going to know?

 

[Trevorleach]

150 litre tank, bottom of it is 54degc heated by solar, and top is at 66degc heated by boiler.

 

[Onoff]

On a bit of a side mission at the mo. I want to hit the button and buy a PV set up to go on the SW facing garage roof. @johnser has kindly been talking to me about it.

I was looking at in roof panels.

I've been told "You need to allow perimeters for trays / apron course at the footer and a gap at the top for wind sheer. For MCS anyhoo".

Clearly if the garage didn't have a hip and was a gable end it would be better for ease of layout.

I'm really not sure what to do.

 

[knighty]

how many watts are those panels?

JRC Photovoltaic Geographical Information System (PVGIS) - European Commission

Photovoltaic Geographical Information System (PVGIS)

re.jrc.ec.europa.eu

I'll use 300watts... so 3kw if you install 10, 34' roof slope, 45' Azimuth(?) for exactly south west gives...

2942kwh produced over the year

if you stuck 10 panels on the other side too that side would generate 1942kwh over a year - but generation here will be mostly later in the day

hook them up to the same inverter, so you can easily limit output under 3.8kw (3.8kw and under local electric grid has to accept your install, any more and there's extra paperwork and possible extra cost)

or get an inverter which has ct clamps on your meter tails so it'll let you generate more than 3.8kw but it'll limit itself so it never exports more than 3.8kw (like when you're not home and everyhting is turned off)


I'm guessing you're going to get a solar dump type device (there's loads to pick from now) which will dump excess power into an immersion heater instead of exporting it to the grid?

 

[Onoff]

how many watts are those panels?

£3.5k inc vat for 12x German made Vision panels ( not German Classic panels made in China )

Panels nom £160 each, trays £50 each

“Vision” glass / glass 320w.

Minimum 87% effective at 30years guaranteed. BMW backed warranty / guarantee.

Including in roof trays and nuts / bolts / panel>tray clamps etc.

No inverter

"A grand better off going Chinese, but after 25 years they’ll be heading for scrap".

"We reckon these panels will still be around 50-60%+ effective minimum at 40 years".

 

[knighty]

from talking to people with solar installs, and ok non have been 30 years..... most 10 or 15 years, 20max.... but they've noticed hardly any performance drop off


personally... I'd buy used panels on ebay, fit twice as many for £2k less


even if you lose a few % efficiency you've saved more than enough £ to pay for the electric

 

[Gareth J]

Sorry I didn't reply to the last pm, been a bit busy. If X10 are a bit tight, just go with x8 higher power ones? In roof ones are ok but suffer more from heat build up apparently.

If I were re-roofing, I'd just stick tin on. Quick, cheap and the cheapest and easiest mounting of panels (as far as I know!)

I had considered buying used ones at~£50 EA for 250W. But panel tech has moved on, same size now gets more like 350W. Bigger panels get ~400W. Less mounting hardware and the same watts in a smaller space.

I'm also not too stressed about degradation, not noticed any annual power reductions on two sets 8 and 4years old, despite never being cleaned. It's still a bit early to say anything but am happy to not be able to detect anything yet

 

[knighty]

^^ for new vs used panels....

you can have four or more times as many used panels for the same price new ones?

 

[gaz1]

On a bit of a side mission at the mo. I want to hit the button and buy a PV set up to go on the SW facing garage roof. @johnser has kindly been talking to me about it.

View attachment 338016

I'm really not sure what to do.

i said on post 46 to fit on your garage

you also dont need planning permission either as your keeping the apex point of roof just removing the rear of the garage roof reusing the slates again

or i dont think you need planning permission just to remove the rear of it and replace with apex roof

house you would, do but garage is different your also not taking up much space with the change either as its the same foot print

only the view from the front you would have trouble with

 

[Gareth J]

^^ for new vs used panels....

you can have four or more times as many used panels for the same price new ones?

Depends really on how cheap the used ones are and how much space you have to play with. The power density, labour and mounting brackets make fitting a higher power panel more attractive still. So, unless you have more roof than capacity, can get cheap mounting hardware too and can keep labour costs down, s/h are harder to justify. Can be significantly lower pence per watt though if you can make it work.

 

[knighty]

quick look on ebay, 285w panels are advertised at £65 each... open to odderes so would probably take £50 each on 20

 

[Gareth J]

quick look on ebay, 285w panels are advertised at £65 each... open to odderes so would probably take £50 each on 20

Sounds fairly good but point still stands. For example, I've a roof that can take x12 panels comfortably @285panel, thats 3.4kW. not bad but I went for ones that are 370W; 4.4kW. about double the cost for 1.3x the power. For the same 4.4kW, I'd have to fit x16 old panels and buy 4/3 as much mounting hardware and take longer to do it and I can't do it anyway as there isn't space!

 

[gaz1]

i said on post 46 to fit on your garage

you also dont need planning permission either as your keeping the apex point of roof just removing the rear of the garage roof reusing the slates again

or i dont think you need planning permission just to remove the rear of it and replace with apex roof

house you would, do but garage is different your also not taking up much space with the change either as its the same foot print

only the view from the front you would have trouble with

its permitted development to change a hip roof to an apex roof due to already having an apex part on it already

dosnt come under the same regulations as the house would be

theres no change to the area foot print

note not the same in a restricted conservation area where you will need permission

 

[Onoff]

Just realised I've wandered away from the original thread title into the realms of PV! Thus continuing with that. I shimmied up onto the garage roof this afternoon and accurately measured the SW facing roof side.

Those conifers will need to kept in check!

I feel I've let the side down not having the crack of my ar$e showing!

Measurements are just the tiled area inside of the ridge and hip tiles.

 

[gaz1]

you would be better with a full range of roof

7200 x 3975

 

[Onoff]

you would be better with a full range of roof

7200 x 3975

Seem to recall you suggesting build another hip on the back? As in mirror the front. That would give me a SE facing hip I could get a couple of panels on as well.

 

[gaz1]

ive mostly said put it on the garage roof as your not bound by the council regulations like you are with the house

but if you are putting it on the garage roof then remove that hip and fit an apex in its place as long as the hip is to the rear of the property where the hip part is

the tiles can be refitted back on and the end built up as its permitted development

 

[Onoff]

ive mostly said put it on the garage roof as your not bound by the council regulations like you are with the house

but if you are putting it on the garage roof then remove that hip and fit an apex in its place as long as the hip is to the rear of the property where the hip part is

the tiles can be refitted back on and the end built up as its permitted development

I likely am bound by some regs even on the garage, as I'm in an AONB.

When you say "fit an apex" you mean change the hip to a gable end?

"as long as the hip is to the rear of the property where the hip part is"

???

 

[gaz1]

if the hip part is facing the front of your house you cant change it as your changing the view of the frontage its not liked and many have been made to put it back to original

yes change the hip from a hip to a gable end an apex roof so it becomes a full roof where your panels can be fitted

as long as your not in a conservation area it would come under permitted developement

but with permitted developement your not changing any of the space only the roof area of the garage

its also not bound by the same regulations as what the house would be